With the track and drag use, the OEM clutch is going to fail really quickly. It's unlikely the dealership will fix under warranty nor would I suggest they replace it with another stock piece. It will likely fail again.
Best bet is a good high performance aftermarket clutch, such as the JWT Clutch and Flywheel combo. This setup has proven itself on countless 350Z and 370Z's over the years and very streetable. We have them for $799 including shipping...in stock:
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If you are looking for something that can hold up to extreme track and drag racing use, then you may want to look at the OS Giken Twin Disc. It's quite a bit more expensive and not quite as friendly on the foot. Only you can decide if it's overkill for your usage patterns with the car.
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Let me or Ryan know if we can help.